Where I demand to camp, a person could light off an M-80 and only the trees that fell without making a noise would hear it.
Not everyone likes to pull into a ashole-to-tea-kettle packed campground just in time to start their nightly jackhammer practice hour. Until a poster or responder specifically indicates they run their generator in a populated campground I like to give them the benefit of a doubt.
Having a 4 cylinder Kubota run for hours meant I had to use my head when designing the homestead. Down wind from the perpetual sea breeze which carries what sound is emitted, up the arroyo. My neighbors were amazed that a generator was running 300 ft from their open bedroom window. Even the acute hearing of a 10-year old could not discern noise.
The reason I camp where I do, where I insist I do, is to preclude the possibility of neighbors. Downwind from anyone or any alternative campsite. My 400 HP 855 NTC Cummins is not quiet.
Tiny Hondas like the old 650 and thousand watt make laughingstock out of newer generator claimed noise levels. It specifically includes newer Hondas and Yamahahahahas. A knockdown foam surround would make these little guys utterly silent.
Then there are those folks who would merely suspect someone may be running a generator, walk 300' press their ear against the machine then scream bloody murder. My sarcasm lies not far from the truth.